Several methods are commonly used for the production of glass fibre reinforced plastic pipes. Centrifugal moulding of such pipes involves rotating a tubular mould form about its axis while introducing the resin and short disorientated glass fibres into the mould. This method suffers from the disadvantage that due to the short length and random orientation of the fibres, the pipe produced has less than the attainable axial and tangential strength.
Another known centrifugal moulding method comprises arranging glass fibre filament or mat in the mould form prior to rotating the latter and introducing the resin. While greater strength may be achieved with this method it is more time consuming.